[PATCH v3 1/2] hw/i386/pc: Default to use SMBIOS 3.0 for newer machine models

[Suravee Suthikulpanit]

Currently, pc-q35 and pc-i44fx machine models are default to use SMBIOS 2.8
(32-bit entry point). Since SMBIOS 3.0 (64-bit entry point) is now fully
supported since QEMU 7.0, default to use SMBIOS 3.0 for newer machine
models. This is necessary to avoid the following message when launching
a VM with large number of vcpus.

   "SMBIOS 2.1 table length 66822 exceeds 65535"

Note that user can still override the entry point tyme w/ QEMU option
"-M ..., smbios-entry-point-type=[32|64].

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---
 hw/i386/pc.c         |  5 ++++-
 hw/i386/pc_piix.c    | 14 ++++++++++++++
 hw/i386/pc_q35.c     | 14 ++++++++++++++
 include/hw/i386/pc.h |  2 ++
 4 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index bb62c994fa..fced0ab0eb 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -1770,7 +1770,10 @@ static void pc_machine_set_smbios_ep(Object *obj, 
Visitor *v, const char *name,
 {
     PCMachineState *pcms = PC_MACHINE(obj);
 
-    visit_type_SmbiosEntryPointType(v, name, &pcms->smbios_entry_point_type, 
errp);
+    pcms->smbios_use_cmdline_ep_type =
+        visit_type_SmbiosEntryPointType(v, name,
+                                        &pcms->smbios_entry_point_type,
+                                        errp);
 }
 
 static void pc_machine_get_max_ram_below_4g(Object *obj, Visitor *v,
diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index d5b0dcd1fe..2905b26666 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -199,6 +199,14 @@ static void pc_init1(MachineState *machine,
     pc_guest_info_init(pcms);
 
     if (pcmc->smbios_defaults) {
+        /*
+         * Check if user has specified command line option to override
+         * the default SMBIOS default entry point type.
+         */
+        if (!pcms->smbios_use_cmdline_ep_type) {
+            pcms->smbios_entry_point_type = pcmc->default_smbios_ep_type;
+        }
+
         MachineClass *mc = MACHINE_GET_CLASS(machine);
         /* These values are guest ABI, do not change */
         smbios_set_defaults("QEMU", mc->desc,
@@ -453,6 +461,7 @@ static void pc_i440fx_machine_options(MachineClass *m)
     PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
     pcmc->pci_root_uid = 0;
     pcmc->default_cpu_version = 1;
+    pcmc->default_smbios_ep_type = SMBIOS_ENTRY_POINT_TYPE_64;
 
     m->family = "pc_piix";
     m->desc = "Standard PC (i440FX + PIIX, 1996)";
@@ -476,11 +485,16 @@ DEFINE_I440FX_MACHINE(v8_1, "pc-i440fx-8.1", NULL,
 
 static void pc_i440fx_8_0_machine_options(MachineClass *m)
 {
+    PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
+
     pc_i440fx_8_1_machine_options(m);
     m->alias = NULL;
     m->is_default = false;
     compat_props_add(m->compat_props, hw_compat_8_0, hw_compat_8_0_len);
     compat_props_add(m->compat_props, pc_compat_8_0, pc_compat_8_0_len);
+
+    /* For pc-i44fx-8.0 and older, use SMBIOS 2.8 by default */
+    pcmc->default_smbios_ep_type = SMBIOS_ENTRY_POINT_TYPE_32;
 }
 
 DEFINE_I440FX_MACHINE(v8_0, "pc-i440fx-8.0", NULL,
diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
index 6155427e48..2d1bb5fde5 100644
--- a/hw/i386/pc_q35.c
+++ b/hw/i386/pc_q35.c
@@ -199,6 +199,14 @@ static void pc_q35_init(MachineState *machine)
     pc_guest_info_init(pcms);
 
     if (pcmc->smbios_defaults) {
+        /*
+         * Check if user has specified command line option to override
+         * the default SMBIOS default entry point type.
+         */
+        if (!pcms->smbios_use_cmdline_ep_type) {
+            pcms->smbios_entry_point_type = pcmc->default_smbios_ep_type;
+        }
+
         /* These values are guest ABI, do not change */
         smbios_set_defaults("QEMU", mc->desc,
                             mc->name, pcmc->smbios_legacy_mode,
@@ -359,6 +367,7 @@ static void pc_q35_machine_options(MachineClass *m)
     PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
     pcmc->pci_root_uid = 0;
     pcmc->default_cpu_version = 1;
+    pcmc->default_smbios_ep_type = SMBIOS_ENTRY_POINT_TYPE_64;
 
     m->family = "pc_q35";
     m->desc = "Standard PC (Q35 + ICH9, 2009)";
@@ -387,10 +396,15 @@ DEFINE_Q35_MACHINE(v8_1, "pc-q35-8.1", NULL,
 
 static void pc_q35_8_0_machine_options(MachineClass *m)
 {
+    PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
+
     pc_q35_8_1_machine_options(m);
     m->alias = NULL;
     compat_props_add(m->compat_props, hw_compat_8_0, hw_compat_8_0_len);
     compat_props_add(m->compat_props, pc_compat_8_0, pc_compat_8_0_len);
+
+    /* For pc-q35-8.0 and older, use SMBIOS 2.8 by default */
+    pcmc->default_smbios_ep_type = SMBIOS_ENTRY_POINT_TYPE_32;
 }
 
 DEFINE_Q35_MACHINE(v8_0, "pc-q35-8.0", NULL,
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index c661e9cc80..f754da5a38 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -50,6 +50,7 @@ typedef struct PCMachineState {
     bool i8042_enabled;
     bool default_bus_bypass_iommu;
     uint64_t max_fw_size;
+    bool smbios_use_cmdline_ep_type;
 
     /* ACPI Memory hotplug IO base address */
     hwaddr memhp_io_base;
@@ -110,6 +111,7 @@ struct PCMachineClass {
     bool smbios_defaults;
     bool smbios_legacy_mode;
     bool smbios_uuid_encoded;
+    SmbiosEntryPointType default_smbios_ep_type;
 
     /* RAM / address space compat: */
     bool gigabyte_align;
-- 
2.34.1